Devices and methods for treatment of tissue

ABSTRACT

Delivery systems, and methods using the same, having an ultrasound viewing window for improved imaging and a needle for ablation treatment of target tissues. In an embodiment, the target tissue is a fibroid within a female&#39;s uterus. In an embodiment, the delivery system includes a rigid shaft having a proximal end, a distal end, and an axial passage extending through the rigid shaft. In an embodiment, the axial passage is configured for removably receiving the ultrasound imaging insert having an ultrasound array disposed a distal portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 11/564,164(Attorney Docket No. 025676-000710), filed on Nov. 28, 2006, which was acontinuation-in-part of application Ser. No. 11/409,496 (Attorney DocketNo. 025676-000700), filed on Apr. 20, 2006, the full disclosures ofwhich are incorporated herein by reference.

FIELD OF INVENTION

The present invention relates generally to medical systems and methods.More particularly, the invention relates to delivery systems having anultrasound probe for improved imaging and a curved needle for ablationtreatment, and methods for using the same.

BACKGROUND OF THE INVENTION

Treatment of the female reproductive tract and other conditions ofdysfunctional uterine bleeding and fibroids remain with unmet clinicalneeds. Fibroids are benign tumors of the uterine myometria (muscle) andare the most common tumor of the female pelvis. Fibroid tumors affect upto 30% of women of childbearing age and can cause significant symptomssuch as discomfort, pelvic pain, mennorhagia, pressure, anemia,compression, infertility, and miscarriage. Fibroids may be located inthe myometrium (intramural), adjacent the endometrium (submucosal), orin the outer layer of the uterus (subserosal). Most common fibroids area smooth muscle overgrowth that arise intramurally and can grow to beseveral centimeters in diameter.

Current treatments for fibroids include either or both pharmacologicaltherapies and surgical interventions. Pharmacological treatments includethe administration of medications such as NSAIDS, estrogen-progesteronecombinations, and GnRH analogues. All medications are relativelyineffective and are palliative rather than curative.

Surgical interventions include hysterectomy (surgical removal of theuterus) and myomectomy. Surgical myomectomy, in which fibroids areremoved, is an open surgical procedure requiring laparotomy and generalanesthesia. Often these surgical procedures are associated with thetypical surgical risks and complications along with significant bloodloss and can only remove a portion of the culprit tissue.

To overcome at least some of the problems associated with open surgicalprocedures, laparoscopic myomectomy was pioneered in the early 1990's.However, laparoscopic myomectomy remains technically challenging,requiring laparoscopic suturing, limiting its performance to only themost skilled of laparoscopic gynecologists. Other minimally invasivetreatments for uterine fibroids include hysteroscopy, uterine arteryablation, endometrial ablation, and myolysis.

While effective, hysterectomy has many undesirable side effects such asloss of fertility, open surgery, sexual dysfunction, and long recoverytime. There is also significant morbidity (sepsis, hemorrhage,peritonitis, bowel and bladder injury), mortality and cost associatedwith hysterectomy. Hysteroscopy is the process by which a thin fiberoptic camera is used to image inside the uterus and an attachment may beused to destroy tissue. Hysteroscopic resection is a surgical techniquethat uses a variety of devices (loops, roller balls, bipolar electrodes)to ablate or resect uterine tissue. The procedure requires the fillingof the uterus with fluid for better viewing, and thus has potential sideeffects of fluid overload. Hysteroscopic ablation is limited by itsvisualization technique and thus, only appropriate for fibroids whichare submucosal and/or protrude into the uterine cavity.

Uterine artery embolization was introduced in the early 1990's and isperformed through a groin incision by injecting small particles into theuterine artery to selectively block the blood supply to fibroids andrefract its tissue. Complications include pelvic infection, prematuremenopause and severe pelvic pain. In addition, long term MRI datasuggests that incomplete fibroid infarction may result in regrowth ofinfarcted fibroid tissue and symptomatic recurrence.

Endometrial ablation is a procedure primarily used for dysfunctional (orabnormal) uterine bleeding and may be used, at times, for management offibroids. Endometrial ablation relies on various energy sources such ascryo, microwave and radiofrequency energy. Endometrial ablation destroysthe endometrial tissue lining the uterus, and although an excellentchoice for treatment of dysfunctional uterine bleeding, it does notspecifically treat fibroids. This technique is also not suitabletreatment of women desiring future childbearing.

Myolysis was first performed in the 1980's using lasers or radiofrequency (RF) energy to coagulate tissue, denature proteins, andnecrose myometrium using laparoscopic visualization. Laparoscopicmyolysis can be an alternative to myomectomy, as the fibroids arecoagulated and then undergo coagulative necrosis resulting in a dramaticdecrease in size. As with all laparoscopic techniques, myolysistreatment is limited by the fact that it can only allow forvisualization of subserosal fibroids.

Needle myolysis uses a laparoscope, percutaneous, or open technique tointroduce one or more needles into a fibroid tumor under direct visualcontrol. Radio frequency current, cryo energy, or microwave energy isthen delivered between two adjacent needles (bipolar), or between asingle needle and a distant dispersive electrode affixed to the thigh orback of the patient (unipolar). The aim of needle myolysis is tocoagulate a significant volume of the tumor, thereby cause substantialshrinkage. The traditional technique utilizes making multiple passesthrough different areas of the tumor using the coagulating needle todestroy many cylindrical cores of the abnormal tissue. However, thedesirability of multiple passes is diminished by the risk of adhesionformation which is thought to escalate with increasing amounts ofinjured uterine serosa, and by the operative time and skill required.Myolysis can be an alternative to myomectomy, as the fibroids arecoagulated and then undergo coagulative necrosis resulting in a dramaticdecrease in size. Myolysis is generally limited by its usage with directvisualization techniques, thus being limited to the treatment ofsubserosal fibroids.

To overcome the limitations of current techniques, it would be desirableto provide a minimally invasive approach to visualize and selectivelyeradicate fibroid tumors within the uterus. The present inventionaddresses these and other unmet needs.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to delivery systems, and methods usingthe same, having an ultrasound probe for improved imaging and a needlefor ablation treatment of target tissues. In an embodiment, the needleis curved with the ultrasound probe having an ultrasound array at adistal portion. In an embodiment, the needle is a curved needle.Typically, the needle will be deployed from within a natural or createdbody cavity or body lumen. Exemplary body cavities include the uterus,the esophagus, the stomach, the bladder, the colon, and the like.Exemplary body lumens include the ureter, the urethra, fallopian tubes,and the like. Created body cavities include insufflated regions in theabdomen, the thoracic cavity, regions around joints (for arthroscopicprocedures), and the like. The present invention will generally not finduse with procedures in blood vessels or other regions of thevasculature. Thus, while the following description will be directedparticularly at procedures within the uterus for detecting and treatinguterine fibroids, the scope of the present invention is not intended tobe so limited. In an embodiment, the target tissue is a fibroid within afemale's uterus.

In an embodiment, a rigid delivery system comprises a rigid deliveryshaft, an imaging core, and an interventional core. In an embodiment,the rigid shaft having a proximal end, a distal end, and an axialpassage extending through the rigid shaft. The axial passage willtypically extend the entire length of the shaft from the proximal to thedistal end, and is open at least at the proximal end. The shaft willusually be rigid along all or a portion of its length, but in otherinstances may be flexible, deflectable, or steerable.

In an embodiment, the imaging core preferably comprises an ultrasoundimaging insert or probe disposed within the axial passage, usually beingremovably disposed so that it may be removed and replaced to permitsterilization and re-use. The imaging insert will have an ultrasoundarray within a distal portion thereof. In an embodiment, the ultrasoundarray is tilted relative to a shaft axis so as to provide an enhancedfield of view, as discussed in more detail below. The ultrasound arraymay be tilted at an angle in a range from about 7 degrees to about 15degrees, preferably in a range from about 7 degrees to about 10 degrees.It will be appreciated that the interventional core may be adapted forany conventional form of medical imaging, such as optical coherencetomographic imaging, direct optic visualization, and as such is notlimited by ultrasonic imaging.

In an embodiment, the ultrasound imaging insert further comprises a flatviewing window disposed over the ultrasound array at the distal portion.The distal end of the rigid shaft may comprise a mechanical alignmentfeature, as for example, a flat viewing surface for axial or rotationalorientation of the ultrasound imaging insert within the shaft. The flatviewing surface will be visually transparent to permit imaging fromwithin the axial passage by the imaging insert. It will be appreciated,however, that the transparent visualization window which aids inphysical alignment does not have to be visually transparent forultrasound. For example, at least a portion of the flat viewing surfacemay be composed of an ultrasonically translucent material to permitultrasonic imaging though the surface of the shaft. Further, there-usable ultrasound imaging insert may be acoustically coupled to theouter delivery shaft to ensure that the ultrasound energy effectivelypasses from one component to the other. Ultrasonic acoustic coupling maybe accomplished in several ways by one or a combination of means,including a compliant material (e.g., pad, sheet, etc.), fluid (e.g.,water, oil, etc.), gel, or close mechanical contact between the rigidshaft and ultrasound imaging insert.

In an embodiment, the rigid delivery shaft preferably has a deflectableor fixed pre-shaped or pre-angled distal end. The delivery shaft distalend may be deflected or bent at an angle in a range from about 0 degreesto about 80 degrees relative to the shaft axis, preferably in a rangefrom about 10 degrees to about 25 degrees. The ultrasound imaging insertwill usually be flexible (and in some instances deflectable orsteerable) so that the distal portion of the ultrasound imaging insertis conformable or bendable to the same angle as the shaft deflectabledistal end. The cumulative effect of array tilting and shaft bendingadvantageously provides an enhanced viewing angle of the ultrasoundimaging insert, which is in a range from about 7 degrees (i.e., angledue to tilted ultrasound array) to about 90 degrees relative to theshaft axis.

In a preferred embodiment, the viewing angle is about 20 degrees,wherein the array tilting and shaft bending are at about 10 degreesrespectively. It will be appreciated that several geometries of arraytilting and shaft bending may be configured so as to provide the desiredviewing angle (e.g., distally forward direction, side-viewing or lateraldirection), as for example, viewing of the end within the uterus (e.g.,cornua and fundus).

In an embodiment, the interventional core preferably comprises a curvedneedle coupled to the rigid shaft via a needle guide. Significantly, anangle of needle curvature is dependent upon (e.g., inverselyproportional to) the ultrasound array tilt and the shaft bend. Forexample, an increase in an angle of array tilting or shaft bendingdecreases an angle of needle curvature. This in turn provides severalsignificant advantages such as allowing a treating physician or medicalfacility to selectively choose an appropriate needle curvature basedupon such indications (e.g., variability in needle curvature). Further,a decrease in the angle of needle curvature provides for enhancedpushability, deployability, and/or penetrability characteristics as wellas simplified manufacturing processes. The angle of needle curvature maybe in a range from about 0 degrees to about 80 degrees relative to anaxis, preferably the angle is about 70 degrees when the viewing angle isabout 20 degrees. The curved needle generally comprises a two-piececonstruction comprising an elongate hollow body and a solid distal tip.The solid tip may comprise an asymmetric or offset trocar tip. Forexample, the tip may comprise a plurality of beveled edges offset at avariety of angles. It will be appreciated that the needle may take on avariety of geometries in accordance with the intended use.

In an embodiment, the needle extends adjacent an exterior surface of therigid delivery shaft. In an embodiment, the needle is disposed within aneedle guide which extends along an exterior of the rigid shaft. Thecurved needle may be removably and replaceably disposed within the guidepassage. The guide passage will typically extend approximately theentire length of the shaft and be open at least at the distal end so asto allow the needle to be reciprocatably deployed and penetrated intoadjacent solid tissue. In an embodiment, the needle has a hollow bodyand a solid distal tip formed from conductive material. The needle,optionally, may be covered, at least along a distal portion of theneedle body, with a sheath. In an embodiment, the sheath is retractablesuch that the needle distal tip is extendable from a sheath's distal endthereby adjusting the length of the exposed conductive distal tip. In anembodiment, the sheath is formed from non-conductive material such asparylene.

In an embodiment, the curved needle and needle guide have a flattenedoval shape that has a wideness that is greater than a thickness. Thisoval cross sectional shape is intended to inhibit lateral deflectionduring deployment or penetration of the needle. The needle is configuredto deliver to the target site radio frequency energy (or other ablativeenergy such as, but not limited to, electromagnetic energy includingmicrowave, resistive heating, cryogenic) generated at a relatively lowpower and for relatively a short duration of active treatment time.

In an embodiment, a delivery system includes a shaft, an imaging core,and an interventional core. The delivery shaft has a proximal end, anangled distal tip, and an axial passage therethrough. The imaging corecomprises an ultrasound imaging insert disposed within the axialpassage. The imaging insert has an ultrasound array within a distalportion thereof, wherein the ultrasound array is tilted relative to ashaft axis. The interventional core comprises a curved ablation needlecoupled to the shaft. An angle of needle curvature may be inverselyproportional to the ultrasound array tilt and tip angle.

As discussed above, the geometries of the shaft, imaging insert,treatment needle, and needle guide may be varied in accordance with theintended use. The delivery shaft, ultrasound imaging insert, treatmentneedle, and/or needle guide may be integrally formed or fixed withrespect to one another or preferably comprise separate, interchangeablemodular components that are coupleable to one another to permitselective sterilization or re-use, and to permit the system to beconfigured individually for patients having different anatomies andneeds. For example, a sterilizable and re-usable ultrasound insert maybe removably positioned within a disposable shaft.

The target site undergoing treatment may be any target site which maybenefit from the treatment devices and methods according to the presentinvention. Usually the target site is a uterus within a female's body.The target site in need of treatment generally has an initial (e.g.,prior to treatment) approximate diameter which is greater than about two(2) centimeters (“cm”). Usually, the target site's initial diameterranges from about 1 to about 6 cm. Normally the initial untreateddiameter is about 2 cm.

In an embodiment of methods according to the present invention forvisualization and ablation of fibroid tissues needing treatment within apatient's body include providing a visualization and ablation systemaccording the device and system embodiments described herein. In anembodiment, the method comprises inserting a rigid shaft having aproximal end, a distal end, and an axial passage therethrough within auterus. The distal end of the rigid shaft may then be selectivelydeflected. An ultrasound imaging insert may then be loaded within theaxial passage prior to, concurrent with, or subsequent to shaftinsertion, wherein a distal portion of the insert conforms to thedeflected shaft distal end. Loading may further involve axially orrotationally aligning the ultrasound imaging insert within the rigidshaft. A needle curvature is then selected by the physician or medicalfacility from a plurality of needles (i.e., at least two or more) havingdifferent curvatures based on at least an angle of the deflected shaftdistal end. The selected curved needle is then loaded along the rigidshaft. Under the guidance of the imaging system, the needle is insertedinto the tissue site. The RF generator is set to deliver and/or maintaina target temperature at the target site for a treatment period.

In an embodiment, the ultrasound array may be tilted or inclined withinthe distal portion of the insert, wherein selecting the needle curvaturefurther comprises accounting for the ultrasound array tilt. As describedabove, the ultrasound array is preferably tilted at an angle in a rangefrom about 7 degrees to about 10 degrees relative to a shaft axis.Deflecting will typically comprise pulling a pull or tensioning wirecoupled to the shaft distal end in a proximal direction. Deflectionoccurs at an angle in a range from about 0 degrees to about 80 degreesrelative to the shaft axis, wherein the needle curvature is in a rangefrom about 0 degrees to about 90 degrees (i.e., in the case of anon-tilted ultrasound array) relative to an axis. The method furthercomprises imaging the uterus with a viewing angle of the ultrasoundarray in a range from about 0 degrees to about 90 degrees (i.e., in thecase of a straight needle) relative to the shaft axis, wherein theviewing angle is based upon the deflected shaft distal end and thetilted ultrasound array. It will be appreciated that torquing and/orrotating the rigid device in addition to tip deflection and ultrasoundtilt will allow a physician to obtain the desired viewing plane.

In some embodiments, methods further include ablating a uterine fibroidwithin the uterus with the selected curved needle. In those cases, theneedle may be a radiofrequency (RF) electrode, a microwave antenna, acryogenic probe, or other energy delivery or mediating element intendedfor ablating or otherwise treating tissue. The distal tip of the needlewill usually be adapted so that it will self-penetrate into the tissueas it is advanced from the needle guide. The direction of advancementwill be coordinated with the imaging field of the ultrasound insert sothat the penetration of the curved needle can be viewed by thephysician, usually in real time. Further, an electrolyte (e.g., saline)or other agent may be infused within the uterus prior to or concurrentlywith fibroid ablation so as to enhance the therapeutic effect providedby the treatment needle. This is preferably accomplished by providing atleast one or more (e.g., two, three, four, five, etc.) infusion holes orapertures on the needle body. In still other cases, the needle could bea hollow core needle intended for sampling, biopsy, otherwise performinga diagnostic procedure.

In an embodiment, the power and temperature are generated by a radiofrequency energy generator. The radio frequency energy generator isgenerally configured to deliver energy at a power from about 1 to about50 watts (“W”), generally from about 1 to about 40 W, usually from about20 to about 40 W, and normally about 30 W. The radio frequency energygenerator is further configured to provide a target temperature at thetarget site ranging from about 50 to about 110 degrees Celsius (“° C.”),usually from about 60 to about 100° C., normally about 90° C. In anembodiment, the needle's conductive tip is at approximately bodytemperature as it is initially disposed within the patient's body.

In an embodiment, the target site is treated for a period of timeranging from about 1 to about 10 minutes, generally from about 1 toabout 8 minutes, usually from about 3 to about 8 minutes, normally about6 minutes.

In an embodiment, at least one fluid lumen extends along the rigid shaftfor delivering fluids to a distal portion of the delivery system. The atleast one fluid lumen may be configured for delivery of any one or moreof fluids such as those for enhancing acoustic coupling between theultrasound imaging insert and the target site, contrasting dyes,therapeutic agents, and the like. In an embodiment, the at least onefluid lumen includes acoustic coupling lumens including an internallumen extending along the axial passage and terminating at an internalport within its distal end and an external lumen extending along theaxial passage and terminating at an external port in fluid communicationwith the outside of the axial lumen. In an embodiment, the externallumen is formed by an external hollow tubular body extending along theneedle guide, while the internal lumen is formed by an internal hollowtubular body extending along the underside of the axial hollow tubularbody forming the axial passage. It should be appreciated, however, thatthe external and internal fluid lumens may be oriented in any othersuitable location along the shaft. In the embodiment, as shown, theexternal lumen is located along the needle guide such that the fluid mayexit near the ultrasound window, while the internal lumen extends alongthe underside of the axial hollow tubular body which forms the axialpassage so as to allow the fluid to be delivered to the inner tipwithout trapping air inside the shaft.

In an embodiment, the present invention includes a visualization andablation system generally having a delivery device, an ultrasoundimaging probe detachable from the delivery system, a radio frequencyenergy generator, and an ultrasound system.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings should be read with reference to the detaileddescription. Like numbers in different drawings refer to like elements.The drawings illustratively depict embodiments including features of thepresent invention. The drawings are not necessarily drawing to scale andare not intended to limit the scope of the invention.

FIGS. 1A through 1E illustrate an exemplary delivery system embodyingfeatures of the present invention and having an inclined ultrasoundarray for improved imaging and a curved needle for ablation treatment.

FIGS. 2A through 2D illustrate exploded views of the distal portion ofthe ultrasound imaging insert of FIG. 1A in a straight configuration.

FIGS. 3A through 3D illustrate exploded views of the distal portion ofthe ultrasound imaging insert of FIG. 1A in a bent configuration.

FIGS. 4A through 4E illustrate cross-sectional views of the embodimentsof exemplary delivery system of FIGS. 1A through 1C taken along theirrespective lines.

FIG. 5A illustrates a visualization and ablation system embodyingfeatures of the present invention.

FIG. 5B illustrates features of an exemplary ultrasound probe of thevisualization and ablation system of FIG. 5A.

FIG. 5C illustrates features of an exemplary ultrasound system of thevisualization and ablation system of FIG. 5A.

FIG. 5D illustrates features of an exemplary radio frequency energygenerator of the visualization and ablation system of FIG. 5A.

FIG. 5E illustrates the visualization and ablation system of FIG. 5A asdisposed during operation within a uterus for the treatment of fibroidsin accordance with the features of the present invention.

FIGS. 6A through 6C illustrate the exemplary features of an ablationneedle for use with the visualization and ablation system of FIG. 5A.

FIGS. 7A through 7D illustrate the exemplary features of an ablationneedle for use with the visualization and ablation system of FIGS.4A-4C.

FIG. 8A illustrates an exemplary ablation needle for use with thevisualization and ablation system of FIG. 5A and including an insulatingmaterial such as a retractable sheath.

FIGS. 8B through 8C illustrate the needle of FIG. 8A with theretractable sheath in a retracted position.

FIGS. 8D through 8F are cross-sectional views of the needle of FIG. 8Ataken along lines 8D-8D, 8E-8E, and 8F-8F.

FIGS. 9A through 9E further illustrate the asymmetric solid distal tipof FIG. 6A.

FIGS. 10A through 10C illustrate use of the system of FIG. 1A within auterus for the treatment of fibroids in accordance with the principlesof the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1A through 1C, an exemplary delivery system 10embodying features of the present invention is shown having a shaftinclined viewing window 12 for improved imaging and a curved needle 14for ablation treatment of a target site 16 such as fibroid tissues 18(FIG. 3E) within a female's reproductive system. The delivery system 10includes a system distal end 20, a system proximal end 22, and a rigiddelivery shaft 24. Delivery shaft 24 includes a shaft distal end 26 witha bent or deflectable shaft distal tip 28, a shaft proximal end 30, andan axial passage 32 extending longitudinally through at least a portionof the delivery shaft 24. A handle 40 with handle proximal and distalends 42 and 44, is attachable to the shaft proximal end 30. The handle40 further includes a longitudinally movable slider 45 for enabling theadvancement and retraction of the needle 14 to and from within a needleguide 58.

The curved needle 14 has a needle body 50 with a shaped needle distalend 52 and a solid needle distal tip 54, as best seen in FIGS. 1B-1E and4A-E. Needle 14 is configured to deliver, to the target site 16including fibroid 18 (as shown in FIG. 3E), radio frequency energygenerated at a relatively low power and for relatively a short durationof time from an ablative energy generator 400 (such as, but not limitedto, electromagnetic energy including microwave, resistive heating,cryogenic) including a radio frequency (RF) energy generator 410, asshown in and discussed in reference to FIGS. 3A and 3E. In anembodiment, as shown, needle body 50 is a hollow body forming a needlelumen 51.

Now referring back to FIGS. 1A and 1B, needle 14 is disposed adjacentthe exterior of the shaft 24 within the needle guide 58. Needle guide 58includes a guide passage 59 and is attachable to the shaft by way ofadhesive, or other means such as laser welding, shrink tubing, and thelike. Needle 14, as best seen in FIG. 1B, 4B, and 5C, may include one ormore needle apertures 60. As shown, the needle 14 includes two needleapertures 60A and 60B. The most distal aperture 60A exposes the distalend of a thermocouple pair 59 a and 59 b as shown in FIG. 6C. Theproximal aperture 60B may be used for delivery of various therapeuticand/or imaging enhancement fluids and contrasting agents/dyes to thetarget site 16 and fibroid 18. In the embodiment shown, contrasting dyeruns within the lumen 51 of the hollow needle body. As can be seen fromFIGS. 2A and 4C, the thermocouple pair 59 a and 59 b are disposed withinthe lumen 51 for monitoring the temperature at the target site 16, whilethe annular space around the thermocouples within lumen 51 is usable fordelivery of dyes.

The shaft axial passage 32 is configured for removably and replaceablyreceiving and housing an ultrasound imaging insert 70. A sealing element72 may be provided between the ultrasound imaging insert 70 and theshaft handle 40 to provide sufficient sealing around the imaging insert70 at a proximal end.

The ultrasound imaging insert 70 as shown in FIG. 1B, and as furtherdescribed below, comprises an insert flexible shaft 74, an insertproximal end 76, an insert distal end 78, an ultrasound array 80, and aninsert flat viewing window 82 disposed at the insert distal end 78. Theultrasound array 80 is viewable from the shaft inclined viewing window12. The shaft viewing window may be used for axial and/or rotationalorientation of the ultrasound imaging insert 70 within the deliverysystem shaft 24. A simplified illustration of the delivery shaft 24 asshown in FIG. 1D carries the ultrasound imaging insert 70 within itsaxial passage 32. A viewing plane 11 provided by the tilted and bentultrasound array 80 is further illustrated.

Referring now to FIGS. 2A through 2D, exploded views of a distal portion71 of the ultrasound imaging insert 70 are illustrated. FIGS. 2A and 2Cshow isometric and side views respectively of the ultrasound imaginginsert 70 in a straight position prior to insertion into the axialpassage 32 of the delivery shaft 24, as will be described in more detailbelow. The ultrasound imaging insert 70 comprises a flexible shaft 74and includes an ultrasound array 80 and a flat viewing window 82 withinthe distal portion 71. FIGS. 2B and 2D illustrate transparent isometricand side views respectively of the ultrasound imaging insert 70, whereinthe ultrasound array 80 is shown tilted relative to a shaft axis 39.Preferably, the ultrasound array 80 is tilted or inclined at an angle αin a range from about 7 degrees to about 15 degrees. It will beappreciated that the angle α of inclination of the ultrasound array 80may comprise a variety of angles (e.g., 0 degrees to about 45 degrees)as permitted by an outer diameter of the flexible shaft 74. Theultrasonic array 80 may be arranged in a phased array, for exampleeither a linear phased array or a circumferential phased array.Alternatively, the ultrasonic imaging array 80 may comprise one or moreindependent elements, such as parabolic or other shaped imagingelements. In still further embodiments, the ultrasonic imaging array 80may be arranged in a rotating mechanism to permit rotational scanning.

Referring now to FIGS. 3A through 3D, exploded views of a distal portion71 of the ultrasound imaging insert 70 are further illustrated. FIGS. 3Aand 3C show isometric and side views respectively of the ultrasoundimaging insert 70 in a bent position subsequent to insertion into theaxial passage 32 of the delivery shaft 24. In particular, thetransparent isometric and side views of FIGS. 3B and 3D illustrate thecumulative effect of tilting the ultrasound array 80 relative to theshaft axis 39 at the angle α and bending the distal portion 71 of theultrasound imaging insert 70. The bend angle β may be in a range fromabout 0 degrees to about 80 degrees relative to the shaft axis 41,preferably in a range from about 10 degrees to about 13 degrees. Thebend angle β will be determined by the deflectable distal tip 28 of thedelivery shaft 24 as the flexible insert 70 conforms to the deflectabledistal tip 28 upon insertion within the shaft 24. The viewing angle κ ofthe ultrasound imaging insert 70 achieved by this cumulative effect maybe in a range from about 7 degrees (i.e., angle due solely to tiltedultrasound array 12) to about 90 degrees relative to the shaft axis 40.In the illustrated embodiment, the viewing angle is about 20 degrees,wherein the array tilting is approximately 7 degrees and shaft bendingis about 13 degrees.

In an embodiment, the deflectable distal tip 28 of the rigid shaft 24may be deflected by the use of pull or tensioning wire(s) housed withinthe shaft 24. Deflection may occur at a true mechanical pivot or at aflexible zone at the shaft distal end 26. When the delivery shaft 24 isdeflectable by a user, various needles 14 may be used to match theamount of deflection provided by the distal tip 28 as well as the amountof tilt provided by the ultrasound array 80. Hence, the needle guide 58will typically be empty until the distal end 26 of the shaft 24 isdeflected. For example, the shaft 24 may be inserted in a straightconfiguration. The distal tip 28 may then be deflected until a targetanatomy is identified. A needle 14 is then back loaded within the guidepassage 58 that corresponds to the amount of the deflection.

The delivery system 10, as shown in various FIGS. 1 and 2, at the deviceproximal end 22, includes a plurality of fluid inlet ports 100 influidic communication with various portions of the delivery system shaft24, needle 14, and/or imaging insert 70. In an embodiment, features ofwhich are shown in FIGS. 1A and 2A, system 10, includes fluid inletports 102, 104, and 106. Fluid inlet ports 100 (including 102, 104, and106) are configured to direct various fluids to a distal portion 23 ofthe delivery system 10. By way of example, fluid inlet port 102 isconfigured to deliver dyes to at least one of the needle apertures 60,such as aperture 60B at the needle distal end 52; while fluid inletports 104 and 106 are configured, respectively, to deliver acousticcoupling fluids through external and internal axial lumens 86 and 88disposed along axial passage 32 to a shaft external fluid outlet port 90and a shaft internal fluid outlet port 92 at the shaft distal end 26.Same or different fluid ports, such as fluid port 102, may be furtherutilized to deliver other fluids such as therapeutic agents to any ofthe other outlet ports or apertures. Optionally, additional aperturesmay be provided at desired locations along lumen 51 of the hollow needlebody 50.

The shaft 24 of the present invention, as described herein, may serveseveral functions including delivering ultrasound, diagnostic, and/orinterventional treatments, bending of the ultrasound insert via thedeflectable distal tip, and/or providing a sterile barrier between theultrasound and/or interventional components. As shown in FIG. 1B, thedelivery shaft 24 carries the ultrasound imaging insert 70 within itsaxial passage 32.

Generally, the delivery system shaft 24 will have a length in a rangefrom about 20 cm to about 40 cm and an outer diameter in a range fromabout 3 mm to about 10 mm, while the ultrasound imaging insert 70 willhave a length in a range from about 50 cm to about 90 cm and an outerdiameter in a range from about 2 mm to about 4 mm. Delivery system shaft24 and the ultrasound imaging insert 70 may be acoustically coupled inone or more of several ways to enable the effective passage ofultrasound energy from one component to the other. For example, theultrasound insert 70 may be placed in close mechanical contact with theshaft 24 so as to provide a dry coupling. In addition or alternatively,a thin compliant layer (e.g., pad or sheet) may be disposed between theviewing windows 82 and 12, of the ultrasound insert 70 and the shaft 24,respectively, so as to provide further interference between suchcomponents. It will be appreciated that a thinner layer may be preferredto minimize unwanted acoustic loss, index of refraction, impedance,and/or other material property effects. Alternatively, or in additionto, the shaft axial passage 32 in which the ultrasound imaging insert 70is disposable, may be filled with a fluid (e.g., water or oil) or gel tofurther provide a wet coupling between the shaft and the imaging insertwhich may compensate for any mechanical tolerances.

Now referring to FIG. 5A, a visualization and ablation system 200embodying features of the present invention is shown, including adelivery device 210, an ultrasound imaging probe 300 being detached fromthe delivery system 210, the radio frequency energy generator 410, andan ultrasound system 500. The various components of the exemplaryvisualization and ablation system 200 will be further described inindividual detail.

The ultrasound probe 300 embodying features of the present invention, asshown in FIG. 5B, generally includes the imaging insert 70 as generallydescribed above, and is connectable to an imaging insert probe port 212at the delivery system proximal end 22. The ultrasound probe 300includes an alignment element 320 for removably engaging with the systemprobe port 212 of the delivery system 210 through a probe cable 310.Alignment element 320 is connectable to the ultrasound system 500 by wayof an ultrasound probe attachment element 330.

The ultrasound system 500, embodying features of the present invention,as shown in FIG. 5C, generally includes a CPU 510 such as one shownoperable by a laptop computer 512. The CPU 510 is connectable to a beamformer 520 by way of a communications cable (such as a firewire cable)such as an ultrasound cable 522. The beam former 520 at a beam formerdistal end 524 is connectable to a probe attachment element 530 by aprobe extension cable 532.

The radio frequency energy 410, embodying features of the presentinvention, and as shown in FIGS. 5D and 5E, is generally connectable tothe delivery system 210 including needle 14, through energy outlet port420. A suitable cable (not shown) removably connects energy outlet port420 to a needle port 413 at the proximal end 22 of the handle 40.Radiofrequency energy is delivered from the radio frequency generator410 to fibroid 18 at the target site 16 through needle 14 which isdisposed within the needle guide 58.

Now referring to FIGS. 6A-6C, needle 14 embodying features of thepresent invention, is shown disposed within the needle guide 58 whichextends along the exterior of shaft 24. As further shown incross-sectional FIGS. 7B-7D, the curved needle 14 generally comprises atwo-piece construction including the elongate needle hollow body 50 withthe shaped needle distal end 52 and the solid needle distal tip 54. Theneedle distal tip 54 may be laser welded 55 to the needle hollow body 50as shown in FIG. 6B. The needle distal tip 54 may also be attached viaalternative means, for example, adhesives or mechanical features orfits. Generally the needle hollow body 50 will have a length 55 in arange from about 20 cm to about 45 cm, an oval cross section having athickness 57 in a range from about 0.5 mm to about 2 mm, and a wideness59 in a range from about 1 mm to about 3 mm. In an embodiment, as shownin FIG. 7B, the oval cross section is flattened minimizing lateraldeflection during deployment or penetration of the needle 14. In anembodiment, as shown in FIGS. 6B and 6C, there are two laser cutinfusion apertures 60 within the tubular body 50 for the infusion ofagents (e.g., electrolytes, drugs, etc., dyes/contrasts) so as toenhance either or both the visualization and therapeutic effect of theneedle 14 prior to, during, or after the ablation treatment. Theinfusion apertures 60 may be aligned on one side of the tubular body 50.Generally, the infusion apertures have a length 63 in a range from about0.5 mm to about 2 mm and a width 65 in a range from about 0.5 mm toabout 2 mm.

As best seen in FIG. 7A, the hollow tubular body 58 may be curved at anangle θ in a range from about 0 degrees to about 80 degrees relative toan axis 65 so as to access side/lateral fibroids. In this depiction, theangle θ is about 70 degrees. Significantly, the angle of needlecurvature θ is dependent upon the ultrasound array tilt angle α and theshaft bend angle β. For example, an increase in the tilt angle α or bendangle β decreases the angle of needle curvature θ. This in turnadvantageously allows a treating physician to selectively choose anappropriate needle curvature from a plurality of needles 14 (i.e., atleast two or more) having different curvature angles θ.

Referring now to FIGS. 9A through 9E, in an embodiment, the solid tip 54may comprise an asymmetric or offset trocar tip. The center point of thetip 54 may be offset from a centerline of the needle to help compensatefor any needle deflections due to tenacious tissue, in effect steeringthe needle towards the intended target even with the deflection. Forexample, the tip 54 may comprise a plurality of beveled edges offset ata variety of angles as illustrated in FIGS. 9D and 9E.

The needle body 50 is formed from an RF energy conductive material suchas stainless steel. As will be appreciated, the solid tip 54 maycomprise a variety of dimensions and shapes and is not limited to FIGS.9A-9E. It will be further appreciated that the tip 54 need not be aseparate component but may alternatively be integrally formed with theneedle body 50. The needle 14, including the tip 54 and tubular body 50may be formed from a variety of materials including stainless steel,nitinol, and the like, for transmitting ablation energy. As best seen inFIG. 1A, the handle 40 may have a needle advancement portion toreciprocatably advance or retract the needle 14 from within the needleguide 58. The needle advancement portion, as shown, is in partiallyadvanced position for complete deployment of the needle 14. The needleguide 58 will further have an oval cross section similar to that of theneedle 14, with a thickness in a range from about 0.5 mm to about 2 mmand a wideness in a range from about 1 mm to about 3 mm. The flattenedguide 58 and flattened needle 14 as shown in FIG. 4C are intended tominimize lateral deflection during deployment or penetration of theneedle 14 into the tissue.

In an embodiment, as shown in FIGS. 8A-8C, an insulating material 140extends longitudinally along at least an exterior portion 142 of theneedle 14 terminating proximal to the conductive needle distal tip 54.In an embodiment, features of which are shown in FIGS. 8D-8E, theinsulating material 140 forms a retractable sheath 144. The conductiveneedle distal tip 54 is extendable from a distal end 146 of theretractable sheath 144. The proximal retraction of the sheath 144 may beused to selectively control the length of the needle distal tip 54. Asshown, the needle distal tip 54 is in a configuration distally extendedfrom the distal end 146 of the retracted sheath 144.

The insulating sheath 140 may be formed from one or more suitableinsulating material such as polyester shrink tubing, and parylenecoating such as parylene C. Generally, the length of the conductivedistal tip 54 ranges from about 1 to about 4 cm, usually from about 2 toabout 3 cm, normally about 2 cm. In an embodiment, the conductive distalend is a T-type active electrode.

Now referring back to FIGS. 5D-E, the radio frequency energy generator410 is configured to deliver power to the fibroid 18 at the target site16, in a an amount ranging from about 1 to about 50 W, generally fromabout 10 to about 40 W, usually from about 20 to about 40 W, normallyabout 30 W. In an embodiment, the radio frequency energy generator 410is configured to deliver and/or maintain a target temperature to thetarget site 16 ranging from about 50 to about 110° C., usually fromabout 60 to about 100° C., normally about 90° C.

The target site 16, such as fibroid 18, generally has an initialuntreated diameter greater than about 2 cm, usually from about 1 toabout 6 cm, normally about 2 cm. During the treatment of the fibroid 18,the needle 14 may be inserted one or more times into the tissue as maybe necessary. In an embodiment, the needle distal tip 54, may bedeployed into the tissue, up to 3 cm as measured from the distal end ofthe of the delivery device 10. During the treatment, the deployed lengthof the needle penetrating the tissue is visualized through theultrasound imaging system 500.

By way of operation, in an embodiment, the deflectable distal tip 26 ofthe rigid shaft 24 may be deflected by the use of pull or tensioningwire(s) housed within the shaft 24. In another embodiment, the distaltip may have pre-determined deflection as compared to a longitudinalaxis at a proximal portion of the device. Deflection may occur at a truemechanical pivot or at a flexible zone at the shaft distal end. When thedelivery shaft 24 is deflectable by a user, various needles 14 may beused to match the amount of deflection provided by the distal tip 26 aswell as the amount of tilt provided by the ultrasound array 80. Hence,the needle guide 58 may be empty until the distal end 26 of the shaft 24is deflected. For example, the shaft 24 may be inserted in a straightconfiguration. The distal tip 26 may then be deflected until a targetanatomy is identified. A needle 14 is then back loaded within the guidepassage 70 that corresponds to the amount of the deflection.Alternatively, the needle may be pre-loaded in the shaft to provide asterile and convenient delivery device to the user.

In exemplary embodiments, the therapeutic needle 14 advancement from theguide 58 via needle advancement portion on the shaft handle 40 can beviewed in the ultrasound system 500 in real time as it is penetratedinto the uterine fibroid 18 inside the uterus 17. The therapeutic needle14 may be penetrated in several configurations (e.g., lateral, side,axially extending) depending on the ultrasound viewing angle.Advantageously, tilting of the ultrasound array 80 and angling of thedistal tip 26 allows a treating physician to image most or all of thecornua and fundus of the uterus 17 with a single device 10.

Now referring back to the previous Figures, Table I below illustratespossible viewing angles κ that may be achieved by the cumulative effectsof the shaft bending angle β (e.g., either through active deflection ofthe distal tip or a pre-shaped or pre-bent distal tip) and theultrasound tilting angle α. The matching needle angles θ based on thepossible viewing angles κ are further illustrated. In example 1, theshaft 24 is in a straight configuration so that the viewing angle κ isprovided solely by the tilting angle α of the ultrasound array 80. Inexample 4, the needle 14 will have a straight configuration. In example5, a non-tilted and non-bent ultrasound array 80 version is covered. Itwill be appreciated that the viewing angle κ will be more than the bendangle β of the shaft 24 due to the additive effect of the tilting angleα of the ultrasound array 80. This allows the bend on the distal tip 28of the shaft 24 to be shallower without compromising the cumulativeviewing angle κ, which is of particular benefit for patient insertionconsiderations. In the case of a deflectable distal tip 28 in whichinsertion may be implemented in a straight configuration, the tiledultrasound angle α still aids in reducing the needle angle θ.

TABLE I Viewing Angle Tilt Angle Bend Angle Needle Angle Example  (κ)(α) (β) (θ) 1 7°-10° 7°-10° 0° 80° 2 20° 7°-10° 10°-13° 70° 3 45° 7°-10°35°-38° 45° 4 90° 7°-10° 80°-83°  0° 5  0° 0° 0° 90°

Referring now to FIGS. 10A and 10C, a method, embodying features of thepresent invention, for using the system 10 of FIG. 1A to treat fibroidsor tumors 18 within the uterus 19 is illustrated. Typically, the rigidshaft 24 is inserted in a straight configuration within the uterus 19.The distal tip 28 of the rigid shaft 24 may then be selectivelydeflected by a pull wire. The ultrasound imaging insert 70 may then beloaded within the axial passage 32 of the shaft 24 prior to, concurrentwith, or subsequent to shaft 24 insertion, wherein a distal portion ofthe insert 70 conforms to the deflected shaft distal end 28. Loading mayfurther involve axially or rotationally aligning the ultrasound imaginginsert 70 within the rigid shaft 24. A needle angle θ is then selectedby the physician from a plurality of needles 14 having differentcurvatures based on the shaft bending angle β and the ultrasound tiltingangle α. The selected curved needle 14 is then loaded within the passage59 of the needle guide 58.

In exemplary embodiments, the therapeutic needle 14 advancement from theguide 58 via needle advancement button on the shaft handle 40 can beviewed in real time as it is penetrated into the uterine fibroid 18inside the uterus 19 as illustrated by the viewing plane 11 in FIGS. 10Aand 10B. The therapeutic needle 14 may be penetrated in severalconfigurations (e.g., lateral, side, axially extending) depending on theultrasound viewing angle κ. Advantageously, tilting of the ultrasoundarray 80 and angling of the distal tip 28 allows a treating physician toimage most or all of the cornua and fundus of the uterus 19 with asingle device 10. As shown in FIG. 10C, the device 10 may be configuredso as to provide the desired viewing angle κ (e.g., distally forwarddirection, side-viewing or lateral direction). It will further beappreciated that manipulation of the device 10, as for example, torquingand/or rotating the rigid device 16 in addition to tip deflection β andultrasound tilt α will allow a physician to obtain the desired viewingplanes 11, 11′, 11″. For example, viewing plane 11″ may be achieved ifthe device 10 was rotated 180° about its axis. Further, viewing plane11′ may be achieved by torquing the device 10.

Although certain exemplary embodiments and methods have been describedin some detail, for clarity of understanding and by way of example, itwill be apparent from the foregoing disclosure to those skilled in theart, that variations, modifications, changes, and adaptations of suchembodiments and methods may be made without departing from the truespirit and scope of the invention. Therefore, the above descriptionshould not be taken as limiting the scope of the invention which isdefined by the appended claims.

1. A method for imaging and ablating fibroids in a uterine wall, saidmethod comprising: loading a flexible ultrasonic imaging insert into anaxial passage of a rigid shaft having a deflectable tip; advancing therigid shaft into a uterus; deflecting the deflectable tip of the shaftto position an ultrasonic imaging array on the imaging insert to locatefibroids in the uterine wall; axially advancing a needle from the rigidshaft while viewing the needle and the fibroid using the ultrasonicimaging array; and delivering energy via the needle to ablate thefibroid.
 2. A method as in claim 1, wherein the needle is curved so thatit deflects radially outwardly as it is axially advanced.
 3. A method asin claim 1, wherein the needle is straight.
 4. A method as in claim 1,wherein a distal portion of the imaging insert conforms to thedeflectable tip of the shaft as the tip is deflected.
 5. A method as inclaim 1, wherein the ultrasound imaging insert axially or rotationallyaligns within the rigid shaft.
 6. A method as in claim 1, wherein theneedle comprises an electrode.
 7. A method as in claim 1, furthercomprising infusing an agent into the fibroid using the needle.
 8. Arigid delivery system comprising: a rigid shaft having a proximal end, adistal end, a longitudinal axis, and a passage therethrough, wherein thepassage has a distal end with an alignment feature on an inner surfacethereof; and an ultrasound imaging insert removably disposed within thepassage and having an ultrasound array and an outer engaging surfacewhich rotationally aligns with the alignment feature on the innersurface of the passage when the insert is fully received in the passageof the shaft, wherein the ultrasound array has a field of view with acenter line which is tilted in a distally forward direction relative tothe longitudinal axis and wherein the imaging insert may be removed andreused.
 9. A system as in claim 8, wherein the alignment featurecomprises a flat viewing surface which permits imaging with theultrasound array of the imaging insert.
 10. A system as in claim 8,further comprising a needle deployable from the rigid shaft.
 11. Asystem as in claim 10, wherein the needle is deployable within the fieldof the ultrasound array.
 12. A system as in claim 11, wherein the needleis straight when carried in the rigid shaft and curves as it isdeployed.
 13. A system as in claim 10, wherein the needle comprises anelectrode.
 14. A system as in claim 10, wherein the needle is adapted todeliver an agent to the fibroid.